Coleus plant named ‘UF18-97-2’

ABSTRACT

A new and distinct cultivar of Plectranthus scutellarioides (coleus) named ‘UF18-97-2’, selected for its excellent vigor, lateral branching, uniform overall habit, and intense crimson color in sun and shade. The new coleus cultivar ‘UF18-97-2’ was selected because it has superb vigor with brilliant crimson colored leaves with well-defined chartreuse margins. It does not produce flowers, so leaf abscission is minimized late in the landscape season. What makes it a rare red foliage genotype is that it is extremely vigorous and can easily grow three feet tall and five feet wide in the landscape while maintaining intense deep red color in both sun and shade.

Genus and species: Plectranthus scutellarioides.

Cultivar denomination: The present disclosure relates to coleus cultivar‘UF18-97-2’.

CROSS-REFERENCE TO RELATED APPLICATIONS

N/A.

ACKNOWLEDGEMENT OF FEDERAL RESEARCH SUPPORT

N/A.

BACKGROUND OF THE NEW CULTIVAR

Coleus (previously Solenostemon scutellarioides, now Plectranthusscutellarioides) plants are used as annual bedding plants for thelandscape and mixed containers in summer gardens. Coleus plants arepopular for commercial growers and landscapers because they are easy topropagate and provide fast and reliable attractive foliage color thatperforms well at all points in the perishable garden plant supply chain.Coleus plants are also popular with home gardeners because they are easyto grow in both full sun and partial shade conditions, and require lessmaintenance than many other annual garden plants. From the breederperspective, there is much genotypic variability in coleus because it isa tetraploid with active transposons and there are a number of differentvisible phenotypes including foliage color, leaf shape and size, plantheight, time to flowering, and growth habit.

The coleus breeding program in Gainesville, Fla., was initiated in 2003with an emphasis on developing new clonally propagated cultivars thatare profitable for producers and perform well in consumer gardens withlittle or no care. Using recurrent mass selection and maintaining alarge pool of germplasm our program has released over 85 new cultivarsinto the industry since 2007. The coleus breeding program has focused onscreening for new cultivars with novel leaf colors and shapes, increasedvigor and branching, and late flowering, by conducting greenhouse andfield trials under demanding environmental conditions. Greenhouse trialsunder “lush” conditions that push the plants to grow as fast as possiblewith high amounts of light, high fertility and high temperatures areused because these conditions allow for rapid discernment of growthhabits and vigor characteristics, and also facilitate observation ofplant phenotypes under conditions where greenhouse pathogen and insectpressure is highest. A first group of field trials in Citra, Fla., areplanted in full sun in sand beds with plastic mulch in May-June eachyear with drip irrigation, minimal added fertilizer, and no chemicalcontrol for insects or pathogens. A second group of field trials inCitra, Fla., are planted in 30% shade in sand beds in May-June each yearwith drip irrigation and a minimal amount of slow-release fertilizeradded at planting. These “lean” growing conditions are used in the fieldtrials to screen for plants that grow vigorously and consistently forminimalist gardeners. Coleus produces a better seed crop under “lean”conditions than “lush” conditions, which is useful for makingopen-pollinated seeds. Since data is collected on a large number ofgenotypes (˜600-800 per year), each trial only contains 1-3 plants pergenotype. If a genotype performs poorly in any trial it is automaticallydiscarded from the program, leaving ˜200-250 genotypes in the program aselite stock at the end of each year.

Desirable characteristics that continue to be in demand a decade afterfirst commercial introductions are: (1) foliage color stability in sunand shade; (2) consistent well-branched plant habit; and (3) lateflowering. Improved plants with interesting foliage colors in both fullsun and shade conditions allow for more versatile garden use and morecolor choices for gardeners. Superior well-branched plant habit isimportant throughout the production chain from the propagator/grower tothe consumer, which allows for production of a large number ofvegetative propagules and translates into more manageable plants forproducers during culture and shipping to retail outlets. Once planted inthe garden, these well-branched plants require less management over along season of growth. Late flowering is a desirable characteristicbecause early flowering triggers senescence of the lower leaves anddecreases foliage quality of coleus. Floral induction often slowsvegetative growth, and increases landscape maintenance with manualdead-heading and plant replacement, which is vital to landscapecontractors. Late or ‘no flowering’ genotypes with good branching andstable foliage color that have been developed in Gainesville, Fla., haveperformed well in commercial markets, and continue to attract interestfrom US, European, and Asian gardeners. The plant disclosed herein wasselected because it has many of these desirable traits.

SUMMARY OF THE INVENTION

The present invention relates to a new and distinct cultivar of coleusplant named ‘UF18-97-2’. The new cultivar ‘UF18-97-2’ originated from anopen pollination conducted in May-November 2017 in Gainesville, Fla.between the female coleus plant ‘UF15-23-40’ (not patented) and anunknown male coleus plant. A single seedling was chosen in May 2018 forfurther asexual propagation in Gainesville, Fla. FIG. 1 shows thepedigree of ‘UF18-97-2’.

The new cultivar ‘UF18-97-2’ has been reproduced asexually for overeighteen (18) months through vegetative cuttings and has been found toretain its distinctive characteristics through successive asexualpropagations. ‘UF18-97-2’ was first propagated asexually by meristem tipcuttings in May 2018 in Gainesville, Fla., and has remained true-to-typesince that time.

The new coleus cultivar ‘UF18-97-2’ has not been observed under allpossible environmental conditions. The phenotype of the new cultivar mayvary with variations in environment and cultural practices such astemperature, light intensity, fertilization, irrigation, and applicationof plant growth regulators without any change in genotype.

Plant Breeder's Rights ‘UF18-97-2’ have not been applied for. The newcoleus cultivar ‘UF18-97-2’ has not been made publicly available morethan one year prior to the filing of this application.

‘UF18-97-2’ was selected because of its novel combination of leaf sizeand color and plant habit. The following traits have been repeatedlyobserved and are determined to be the unique characteristics of the newcoleus cultivar ‘UF18-97-2’ when grown under normal horticulturalpractices in Gainesville, Fla. These characteristics in combinationdistinguish ‘UF18-97-2’ as a new and distinct cultivar of coleus:

-   -   1. consistent, brilliant-crimson-colored leaves with        well-defined chartreuse margins;    -   2. vigorous, spreading growth habit resulting in a plant that is        roughly 50% wider than it is tall in the landscape;    -   3. enough vigor to withstand the harsh conditions to which the        plants are subjected in full-sun trials in Gainesville, Fla.        (excellent heat tolerance);    -   4. superior stability in foliage color in both sun and shade        conditions (maintains stable color in all conditions);    -   5. excellent lateral branching when grown as a stock plant, thus        providing ample vegetative propagules for producers; and    -   6. has been observed to have long-season performance in        landscape trials in Gainesville, Fla.

Plants of the new coleus cultivar ‘UF18-97-2’ differ from plants of thefemale parent, ‘UF15-23-40’ in the following characteristics:

-   -   1. ‘UF18-97-2’ has large, broad leaves that are uniformly        colored crimson and chartreuse with crenate margins, whereas        ‘UF15-23-40’ has much smaller leaves colored deep burgundy with        occasional lime green accents with lobed margins;    -   2. ‘UF18-97-2’ occasionally has three leaves present at the        meristem tip instead of the normal two leaves arranged        oppositely; and    -   3. ‘UF18-97-2’ has a robust, well-branched, spreading habit,        whereas ‘UF15-23-40’ is much less vigorous and much more upright        in habit with less lateral branching.

Plants of the new coleus cultivar ‘UF18-97-2’ can be compared to thoseof ‘UF17-50-5’ (U.S. Plant Pat. No. 32,980). On the adaxial surface ofmature leaves of ‘UF18-97-2’, the foliage color is a dark solid red (RHS175B), with no transitioning to a lighter color in the center, and theleaf margin coloration zone is narrower than in ‘UF17-50-5’. On theadaxial surface of mature leaves of ‘UF17-50-5’, the foliage color isdeep maroon (RHS N77A) that transitions to a lighter pinkish color (RHS59C) in the center, and the leaf coloration zone is wider than in‘UF18-97-2’.

DESCRIPTION OF THE FIGURES

The accompanying photographs (as shown in FIGS. 1-3) illustrate theoverall appearance of the new coleus cultivar ‘UF18-97-2’. The colorsshown in these photographs are as true as can be reasonably obtained byconventional photographic procedures. Colors shown in the photographsmay differ slightly from the color values cited in the detailedbotanical description, which accurately describes the colors of the newcoleus cultivar. FIGS. 2 and 3 were taken from plants grown nine (9)weeks from unrooted cuttings in June-August 2020 in a glass-coveredgreenhouse in Gainesville, Fla.

FIG. 1 shows the pedigree of ‘UF18-97-2’;

FIG. 2 shows the growth habit, form, and foliage of ‘UF18-97-2’; and

FIG. 3 shows a close-up of the foliage of ‘UF18-97-2’.

DETAILED BOTANICAL DESCRIPTION OF THE CULTIVAR

The following detailed description sets forth the distinctivecharacteristics of the new coleus cultivar ‘UF18-97-2’. Color referencesare to The Royal Horticultural Society of London (R.H.S.) Colour Chart,2007 (5th Edition).

Description of Growing Conditions

The detailed botanical description was obtained using nine-week-oldplants grown from unrooted cuttings in June-August, 2020, in aglass-covered greenhouse in Gainesville, Fla. The plants were propagatedin mist for ten (10) days after cuttings were stuck, then grown inone-gallon pots for approximately seven and a half additional weeks.

Botanical Description

-   Botanical classification:    -   -   Family.—Lamiaceae.        -   Botanical name.—Plectranthus scutellarioides.        -   Common name.—Coleus.        -   Cultivar.—‘UF18-97-2’.-   Parentage:    -   -   Female or seed parent.—‘UF15-23-40’.        -   Male or pollen parent.—Unknown.-   Propagation:    -   -   Type.—Cuttings; vegetative meristems having at least one            node.        -   Time to initiate roots.—3-4 days.        -   Time to produce a rooted cutting.—7-10 days.-   Root description:    -   -   Root description.—Callus forms in 2-3 days, roots initiate            in 3-4 days and become a highly branched cutting in 7-10            days.        -   Rooting habit.—Fibrous.-   Plant description:    -   -   Plant form.—Upright.        -   Growth habit.—Spreading.        -   Plant height (from top of soil).—30-32 cm.        -   Plant width (horizontal plant diameter).—50-55 cm.        -   Branches.—Quantity per plant: 7-8. Color: RHS 143D (light            green). Texture: Smooth. Pubescence: Not present. Stem            description: Square-shaped stem, 0.9 cm in diameter at the            soil line. Branch diameter: 0.6-0.7 cm at the base of a            27-cm-long branch. Branch length: 25-28 cm. Internode            length: 3-4 cm. Anthocyanin: Not present.-   Foliage description:    -   -   Quantity of leaves per branch.—19-20.        -   Arrangement.—Predominantly opposite, with an occasional            meristem tip with three leaves arranged in a whorl.        -   Fragrance.—Not fragrant.        -   Length.—10-12 cm.        -   Width.—7-8 cm.        -   Shape.—Ovate. Apex: Broadly acute. Base: Attenuate.        -   Margin.—Crenate.        -   Leaf texture (both surfaces).—Smooth.        -   Pubescence floor (both surfaces).—Not present.        -   Venation color.—Upper surface: RHS 59B (dark purple red).            Lower surface: RHS 143C (medium green).        -   Venation pattern.—Upper surface: Reticulate. Lower surface.            Reticulate.        -   Color, immature leaf.—Upper surface: Center: RHS 172A            (medium brown). Margin: RHS N144C (light green). Lower            surface: RHS N143C (medium green).        -   Color, mature leaf.—Upper surface: Center: RHS 175B (medium            brown). Margin: RHS N144A (light green). Lower surface: RHS            145A (light green).        -   Petiole length.—3-3.5 cm.        -   Petiole diameter.—0.2-0.3 cm.        -   Petiole color.—RHS 145A (light green).        -   Petiole texture.—Smooth, no pubescence.-   Flowers and seeds: Flowers and seeds have not been observed to date    during formal trials in Gainesville, Fla.-   Fruit/seed set: Fruit and seeds have not been observed to date    during formal trials in Gainesville, Fla.-   Disease and insect resistance: Disease and insect resistance is    typical of the species, thus no claims are made of any superior    disease or insect resistance with this cultivar. The most common    insect pests observed on this plant in Gainesville, Fla., have been    long-tailed or citrus mealybugs (Pseudococcus sp.), which occur on    older stock plant material held in the greenhouse for over 3-4    months. Impatiens Necrotic Spot Virus (Bunyaviridae) has also been    observed in plants confined in greenhouses with mixed crops    (peppers) infected with Western flower thrips (Frankliniella    occidentalis). The most common pathogen of this species in the U.S.    is downy mildew (Pernonspora lamii). This pathogen has been observed    in stock materials grown closely together in cooler growing seasons.

What is claimed is:
 1. A new and distinct Plectranthus scutellarioidesplant named ‘UF18-97-2’ as shown and described herein.